Do I need Dyno?

[Red Mist_imp]

PCV maybe not "obsolete" , I do see the overlap, but PCV is safer and keeps the warranty in place, PCV can be removed in 5 minutes, not so with ECU flash.
So if you're going to get an ECU flash, skip PCV, but PCV is still a nice upgrade I am glad I have one.... of course, if I do get the ECU flash, I would try selling the PCV.

Reflash does not void warranty. However it is not always EPA legal depending on the state. The ECU can be flashed back to stock just as easily modified.